In today's world, it is hard for people to get the sleep their bodies need. Now a new study has found that not getting enough sleep can be linked to more aggressive types of breast cancer in women who have been diagnosed with the disease.
The study is reported in the journal "Science Daily."
Researchers looked over medical records and surveys from more than 400 post-menopausal breast cancer patients.
They were asked about their sleep patterns in the last two years. Researchers found women who got six hours of sleep or less each night had a higher recurrence of tumors. They were unable to find a similar link in pre-menopausal women.